Archivists at a New York college library stumbled upon an intimate artifact of George Washington — a lock of his iconic grey hair, tucked in an 18th-century almanac.

The rare find has Schenectady's Union College revisiting its relationship with the first president of the United States as historians wonder how the hair made it there.

Historical records project archivist Daniel Michelson found the almanac atop a bookshelf at the college's Schaffer Library. The leather-bound book, titled Gaines Universal Register or American and British Kalendar for the year 1793, includes population estimates of the American colonies.

Inside the book, the college said, was an envelope, which read "Washington's hair, L.S.S. & (scratched out) GBS from James A. Hamilton given him by his mother, Aug. 10, 1871." The hair was inside the envelope, tied together by a thread.

The book belonged to Philip J. Schuyler, son of one of the college's founders, Gen. Philip Schuyler, a friend of Washington's. Historians and authors suggest Martha Washington gave the hair to Eliza Schuyler Hamilton, wife of Alexander Hamilton, who later passed it on to family members.

A lock of hair used to be given as a keepsake, said Susan Holloway Scott, author of I, Eliza Hamilton.

The college concedes it can't definitively prove the hair was Washington's and does not know how it came to be at the library. Although, the college reported, manuscripts dealer John Reznikoff believes its "100% authentic."

It's likely worth between $2,000 and $3,000, he added, and is "undoubtedly George Washington's."

The college now plans to preserve the hair and put it on display.

"As an archivist, we come across interesting material all of the time," said India Spartz, Union's head of special collections and archives. "But this is such a treasure for campus."